[Mechanisms of non-specific prothrombin activation].

The review of different mechanisms of non-physiological non-specific prothrombin activation is given as compared with the specific activation by the factor Xa. The use of snake venom enzymes or staphylocoagulase makes possible the thrombin generation from pathological forms of prothrombin lacking of gamma-carboxyglutamic acid and incapable of complete activation into thrombin by the specific activator, factor Xa. This fact stimulated the use of non-specific activators in medicine. Investigation of non-specific prothrombin activators made possible to reveal and to trace pathways of the formation of thrombin active site. It is demonstrated that prothrombin, like other serine proenzymes (trypsinogen, chymotrypsinogen), has already formed active site. This site can be revealed under changes of the conformation of the prothrombin molecule due to the chemical modification or the complex formation with staphylocoagulase.